Heat a large nonstick skillet over medium heat. Swirl in the oil, then add the onion, pepper, and garlic. Cook, stirring occasionally, until softened, about 5 minutes. Stir in the chili powder, oregano, and mustard; let cool 1 minute.

Add the turkey and cook, stirring to break up the meat, until no longer pink, 3–4 minutes. Stir in the barbecue sauce and cook until slightly thickened, about 2 minutes. Remove from the heat and serve in the hamburger rolls.

Good ideaIt's important not to overcook the ground turkey breast in this recipe or it may become dry and chewy. Keep it moving in the pan, and add the sauce as soon as it is cooked through—not browned.